1. Field of the Invention
The present invention relates to a printing system composed of a printing apparatus and a printing control apparatus.
2. Description of the Related Art
In recent years, a printing system (an image forming apparatus or a combination of the image forming apparatus and a printing control apparatus) having functions for realizing an improvement in efficiency of power consumption and power saving is demanded as efforts to deal with environmental issues. One of the functions is a sleep mode function. This sleep mode refers to a stop state in which power supply is stopped to an unused function in a case where an image forming apparatus does not have a communication from an external communication terminal for a certain period of time, and only minimal power is supplied while a printing execution and a display of an operation screen are stopped.
To effectively utilize this sleep mode function, according to a technology in related art (for example, see Japanese Patent Laid-Open No. 2009-287889), a technique of temporarily storing a print job having a low priority in another storage area is proposed. With this proposal, the following situation is avoided. That is, a print job having a low priority on the execution is intermittently executed, the return from the sleep mode frequently occurs, and as a result, a reduction in consumption power during the shift to the sleep state is not effective.
However, according to the technology in related art described in Japanese Patent Laid-Open No. 2009-287889, the image forming apparatus switches storage destinations of the job depending on the previously set priority of the job to minimize the intermittent execution but does not take a condition into account as to whether or not a job that is actually impeditive to the sleep itself exists.
The printing system composed of the image forming apparatus and the printing control apparatus is configured to detect the presence or absence of a job reception or a query from the printing control apparatus to which the image forming apparatus is connected and the other external communication terminals. As a result of the above-described detection, the image forming apparatus enters the sleep mode in a case where the communication with the external apparatus or the reception does not exist for a certain period of time. The image forming apparatus periodically receives a use state of the printing control apparatus to determine whether or not the image forming apparatus can enter the sleep mode. While the image forming apparatus receives the use state indicating that the printing control apparatus is in use (active state), the image forming apparatus is not shifted to the sleep mode. For example, after a job is input to the image forming apparatus, the printing control apparatus waits for a printing completion notification from the image forming apparatus and determines that the job is ended. For that reason, until the printing is completed, the printing control apparatus continues notifying the image forming apparatus that the printing control apparatus is in the active state.
A situation however occurs in which an effective transition to the sleep mode is not conducted in the above-described printing system according to the related art technology where a type of the job is not taken into account.
For example, in a case where printing is started only after a user authentication is conducted in the image forming apparatus like a secure job, the printing control apparatus determines that the image forming apparatus waits for the printing start in a state of waiting for the authentication, and a situation occurs in which the shift to the sleep mode is not conducted even when the image forming apparatus can enter the sleep mode.
Furthermore, in case of a job having a sheet feed waiting standby setting (suspend-on-mismatch setting), the job waiting for the sheet feed remains in a printing queue as a sheet feed waiting suspend job. For that reason, the printing control apparatus continues notifying the image forming apparatus of the active state until an appropriate sheet is fed and the suspend state is cancelled. As a result, the image forming apparatus is not shifted to the sleep mode even in a case where the sheet feed waiting state is continued.